Bear in mind that we summon units in increments of 6 Celestial Conjuration points (CCPs) (6-12-18-24), when you are planning summons. (well, then there is the Dread Saurian for 40 SPs)

SLANN

As a General, a “naked” Slann can collect up to 10 CCPs / turn (3 for each unused spell slot, 1 because of the general). Of course, it makes little sense to have a Slann for summoning and not use it as general.
A Slann typically will come with Great Rememberer (double LoSaT) or Vast Intellect (more selection of useful spells). If you intend to collect summining points, Vast Intellect will go unused, so for a summoning tactic it’s better to have a GR Slann, to exploit the superior mobility granted by a double teleport

LORD KROAK

Same as the Slann: with a starting value of 4 spells, he can easily give 13 summoning points each turn. However, you are taking Kroak because of his unique spells, and I cannot imagine someone that doesn’t cast a comet with Kroak. You are paying 450 pts instead of 260 to have those unique spells, so the summoning potential of Kroak will almost never be fully used. Still solid, though.

ASTROLITH BEARER

This guy gives handy bonuses (increase the spells’ range and gives +1 to cast, useful if you need to effectively cast something, and reroll all to hit within 10”), that just by themselves justify the 160 pts cost. Plus, it gives an additional d3 summoning points.
Slann + AB come at 320 pts cost, and it’s the most basic combo.
If you just don’t cast, in your second turn you will have 20 +2d3 summoning points, so on average you should be able to reach the magic level of 24 summoning points by turn 2.

Endless spell: BALEWIND VORTEX.

An exceptionally useful spell, with solid bonuses, that takes your basic combo Slann+AB to a solid 12 + d3 summoning points /turn.
It costs 40 pts, and gives: increased casting range, a +1 to saves for your Slann (a thing you need), AND an additional spell slot.
With BV, at turn 2 you will have your 24 summoning points for sure (and you could even afford the casting of one spell)

Endless Spell: CHRONOMANTIC COGS

It costs 60 pts, and you can choose between 2 effects: an additional spell, OR +2 to move and charge.
The exceptional utility of this spell, is that the bonus to charge is something that could vastly improve the strategy of summoning (or teleporting) + successfully charge, so if a skink casts the Cogs, you can use the cogs one turn to gain additional SPs, and the charge bonus in the following turn (for example, unless you don’t roll poorly with the 2d3 astrolith, you can summon a Carnosaur at turn 2 and try to immediately charge with +2, so it’s a 7+ rerollable with the use of a command point)

A summoning list can work with just Slann + AB, but every summoning list, should at least include one or both Endless Spells… BUT, as said, they comes with a cost. A Slann + AB + both the spells, cost a whopping 520 pts. At 1000 points, it’s half of the army.

ENGINE OF THE GODS

One of our strongest dinos in the 2nd ed., it doesn’t give Summoning Points, but it’s able to directly summon units by itself, and works in combo with the Slann.
‘nuff said, it is almost an autotake if you run a 2000 pts list… or 2-3 of them, if you wanna be really nasty.

A very basic summoning list, will include just a Slann and an Astrolith bearer
In 2 turns, if you totally forego casting, you can collect 20 + 2d3 CCPs. An average chance to summon a Basti or a carnosaur at turn 2.

Those 24 CCPs / turn 2 will be basically 100% sure, if you have at least one of the endless spells that buffs the casting.

Leaving aside the EotG, a heavy summoning list, will include Slann, AB, Vortex, a Starpriest and a Cogs (that will be casted by the skink, to be used by the Slann).
In 2 turns, if you totally forego casting, you can collect up to 29 + 2d3 CCPs.

Now that we know how many CCPs we can collect, lets go to see what we can conjure...

I'm gonna give a ranking for the units that can be conjured.
We must keep in mind that summoned units have limitations on what they can do in the turn they appear, so the ability to act immediately at full power can push a unit higher that a different unit, even if the second one can be stronger as a whole.

The ranking will be:

Excellent (exceptionally useful, you should always have it at hand)
good (almost always useful, sometime can be a suboptimal choice)suboptimal (can be useful, but it's situational; usually there are better choices)poor (bad unit to summon, useful only under exceptional circumstances)

SUMMONABLE UNITS with 6 Celestial Conjuration Points (CCPs)​

SALAMANDER (Suboptimal)

We all know sallies are a very strong shooting unit. Their rend is solid and their potential damage is huge. But we are not judging the unit by its merit, but by its effectiveness as summonable reinforcement.
Sallies shoot at 9”, summoned units must appear at more than 9” from the enemy, so they simply cannot shoot unless you have some handlers, which you can obtain by wasting 6 CCPs (at the cost of one sally, so I’d say it’s hardly justified) or by having some handlers already on the battlefield (this can be done, as with 40 pts you can have 3 handlers, that give you the flexibility you need for summoning and also a unit that can be teleported upon an objective).
If you don’t have handlers at hand, i think that summoned sallies are not a strong choice. If you have them, they can be raised to "Good"

RAZORDON (Excellent)

You call a unit that shoots a lot and, tnx to its 12” range, can be summoned and shoot at the target.
Razors are just perfect and you should always have them at hand, as they are one of our most useful summonable unit, especially against hordes or things that ignore rend as Nighthaunts.
Just be careful… with 6 points you just summon 1 razordon, which is suboptimal. You should call no less then 2 of them (possibly 3), and for that you need more points.

3 SKINK HANDLERS (Poor)

They work with razors and sallies. With razors you should already have bonuses that grant reroll to hit (Astrolith bearer, to name one), so they will be mostly called to support salamanders… at the cost of one sally.
The summoning of handlers + sallies should be done only under particolar circumstances, when you need to wreck some nasty target with high rend / damage, and if you don’t have better alternatives. So, very situational

10 SKINKS (Good)

By far the most useful unit that you can summon with only 6 CCPs.
They screen, they take objectives, they give battlefield control, they have the great ability Wary Fighters… they are one of the best battleline units of all the game (if you don’t intend so send them into the fray), and so no surprise that they are so useful even when you summon them.
To spam units upon units of skinks to swarm the battlefield (counting on the fact that the enemy cannot simply kill all of them), is a viable tactic BUT be careful: they can take an unguarded objective, but by themselves they cannot conquer it; they can take an objective, but by themselves they cannot hold it.
So, they are an excellent support, but you can hardly plan a tactic with only-skinks summons.

They're heroes with nice abilities, and obviously you should summon the one that serves you better in that particular moment.
They can be especially handy if you are playing a scenario where heroes gain control of objectives.
The real downside is that when you summon them (end of move phase), they can use their ability only in the hero phase of the following turn, which kinda limits their potential.

SAURUS OLDBLOOD / SUNBLOOD / SCARVET ON CO (suboptimal)

As been said for the skink heroes, also these sauri won't be able to use their command abilities when you summon them. Plus, they cannot give the bonuses granted by the same hero in a certain starhost, because they are not that saurus, so they don't work as replacement.
So, you can summon them when you need heroes to control objectives, or if you need to charge something (better to have some bonus to charge, in that case), or some similar task. Basically, they're situational.

SAURUS ETERNITY WARDEN (good)

Let's face it. If you summon it, it's because you need a bodyguard that takes wounds instead of your precious Slann (once the Slann is dead, it's game over if you're playing a summon list).
Basically, you won't ever summon the Warden, but when you do (because of mortal wounds or nasty shooting), then it's golden.

10 x SAURUS WARRIORS (poor)

Saurus warriors work in horde, possibly supported by heroes. A group of 10 won't be able to pick up a normal fight and won't be able to significantly help you. There's literally nothing that a group of 10 saurus can do, that a group of 20 skinks (or 2 x 10 skinks) can't do better. A pity.

5 SAURUS GUARDS (Suboptimal)

I cannot thing to a single case where you could really need 5 guards.
Even in some unlikely scenario involving an Eternity Warden already on the battlefield, there will be other units that will perform the same task in a more efficient way.
However, as Noted by @Canas, even with only 5 wounds, they are still a sturdy unit, with some offensive power, so they can be an efficient, cheap objective grabber, especially if the opponent don't have too much to throw at them.

5 SAURUS KNIGHTS (Suboptimal)

They're not a bad unit (it's probably our most well-rounded battleline), but IMO you should summon them only if you already have at hand something that can buff such a small unit (Starpriest, ScarVet on CO).
They give their best if you are already running a Firelance… they won't get the bonus from the starhost, but at least the buffers you need should already be on the battlefield.

TERRADONS RIDERS (Good)

it's a unit that moves fast and flies; they can shoot, give good battlefield control and are not worthless in cc.
If i'm not ranking them as "exceptional", is because in the turn when you summon them, their contribution is limited. Set them with javelins for harassment of bolas for a more aggressive play.

RIPPERDACTYLS (Exceptional / Suboptimal)

If you have at least a Bloat Toad on the battlefield (and possibly some buffs to charge), then they are exceptional.
If you don't have a Bloat Toad, then they are suboptimal; if you want some flyers, go for Terradons.

5 CHAMELEON SKINKS (Suboptimal)

The nice thing is that by RAW, you can summon them and set them in hiding; in your next turn you can use the ambush ability, without the limitation of 9" away from enemy. Nice, but for niche situations.

When you play summon, you usually need hitters or bodies, because you already have on the battlefield a good amount of support units.
You are gonna pay 18 CCPs for another support character (albeit a very good one), that is not going to help you in the turn you've conjured it.

ASTROLITH BEARER (suboptimal)

you know the guy, gives wonderful bonuses and collects an additional d3 CCPs.
You should already have one on the battlefield… but if she's dead, you are NOT going to spend 18 CCPs for a model that gives you d3 points.
The only real reason why you should ever need to call an AB, is if your AB is dead and you truly need the rerolls to hit in that point of the battlefield, when you are pushing your final effort and the rerolls can make a difference between a victory and a loss.

20 SAURUS WARRIORS (suboptimal)

10 saurus warriors at 12 CCPs are a poor choice. This one is better because of:
1) the discount in price.
2) if you just need a resilient unit to sit and control an objective, they're pretty good at the task.

3 KROXIGORS (suboptimal)

Sadly, with the actual rules, Kroxy are a neglected unit. The good part is that usually they are a weak unit, but with summon you can choose. And obviously you will summon them when you have an horde of small models to face, aka the situation they are made for... at that point the moonhammer can be devastating.
Unless, of course, you cannot call something more good than them to accomplish the same task, like 3 razordons.

TROGLODONT (Exceptional)

On paper the trog is our weakest dinosaur, but it has 2 big advantages.
1)
it costs 18 CCPs, instead of 24
this means that a even a non-dedicated summoning list, can be sure to conjure the beast turn 2.
2)
It's a reliable charger. With an astrolith nearby, he will likely wound a target, gaining +3 to charge. Add some further bonus (constellations, and so on), and you will hit at full health in the turn the Troglodon appears.... and it's cc profile is far from bad. Seriously.

ENGINE OF THE GODS (Good)

It's a toned down stegadon that does wonders with the engine and can summon further bodies on the battlefield.
It's one of our current strongest unit, but I'm not ranking it at the top for 2 reasons:
1) You should already have one or two on the battlefield.
2) You cannot activate the engine in the turn you conjure it, so you are going to lose 1 turn to use the full potential of the EotG…. and given that the summons by the EotG, call units with a 12 CCPs value, you need 3 turns to obtain a positive income.
(the ranking for such a peculiar unit is, of course, debatable: if you manage to summon it in turn 1, then it can be considered exceptional. If you call it turn 4, then it's poor)

OK guys, you all know this is where the good things await.
With a dedicated setting, you will be able to conjure one of these by turn 2.
Be careful: all the 24 CCPs unit wants to enter cc asap, so prepare something that helps them in this regard (Cogs FTW)

BASTILADON (Excellent)

The bastiladon is no more the "must have" dino it was once, but it's still terribly effective.
its goodness comes also with its ability to be conjured with the set-up you need more.
Need Shooting? lasers
Need mortal wounds against amassed enemies? snakes. (in this case, it's truly mandatory to have a bonus to charge, to send your dude into the fray).

STEGADON (Excellent)

As the bastiladon, its usefulness come with the different weaponry.
Need to kill a single target? Bow, and exploit the rerolls granted by the astrolith bearer.
Need to stomp a horde? flamers!
In both cases, it's mandatory to have a bonus to charge, as you cannot use the skink chief ability when conjured, and you WANT your steggy to crush immediately your opponent. With no bonuses to charge, is "only" good.

SAURUS OLDBLOOD ON CARNO (Excellent)

Summon it, point it toward the target, shoot the gauntlet and then release the pain.

SAURUS SCARVET ON CARNO (Good)

Slightly worse than the Oldblood, probably you should summon it only if you plan to use the command ability in the following turn (your main attack with a large number of nearby saurus to be buffed, an astrolith that with the rerolls increases the additional number of additional attacks).

SUMMONABLE UNITS with 40 Celestial Conjuration Points (CCPs)​

DREAD SAURAN (suboptimal)

yeah, it can be done, and certainly the face of your opponent will compensate your effort (especially if you had a Dread Saurian in the army since turn 1, then it's killed and you just conjure it again).
But it will enter late in the game, at most at turn 3, if you sacrifice all the previous turns summoning.
So ask yourself: what else could you do with those 40 pts?

With the long needed changes to the way the EotG works, now its summon it's available again, so it's pretty much an auto-include when you think to a summoning list, especially given the buffs the EotG receives from a Slann, and the Slann is our main general, so they complement each other.

So, it's time to see how EotG works

First of all, I'm not going to examine all the features of the Engine. Suffice to say, it's becoming common to see builds with more than 1 EotG... many include 2 of them, but it's not impossible to see 3 or 4 Engines, to aim for that sweet 18, or to blast away the enemy with long ranged d6 mortal wounds.

Anyway, with Engine(s) on the battlefield, you will also have the chance to summon units, other than the ones conjured by the Slann…. the units called by the Engine don't need CCPs, they are just summoned with the right roll, during the hero phase, so (working in team with your summoner Slann) you can easily spam units upon units, for a grand feast of summon.

As you can see, all of them are worth 12 CCPs; let's see what works best.

RIPPERS

By far, the best unit to summon in turn one. If you manage to roll the summon in your firt turn with the EotG, don't even think to something different. Remember, the EotG summons in the hero phase, so this means you can place one toad together with the rippers (a thing you cannot do with Slann that conjures at the end of the move phase).

TERRADONS

this is your second most useful summon.
after the first turn, you should pick these ones or the Rippers; evaluate at the moment what do you need more.

20 SKINKS

skinks are always good, but if you need small units that swarm the battlefield and take objectives, the ones conjured by the Slann are more cost-efficient.

There are some basic rules, that work for our summoning on a general level.

ONE:

To create a summining list, it requires a good amount of points investment: you can go from 420 pts (Slann + AB), to 820 (Slann, AB, Cogs, Vortex, starpriest, EotG), not counting lists that include Kroak instead of a Slann, or crazyness with 3-4 EotG, that will surpass 1000.
Basically, the majority of those points will do almost nothing, if not summon and give some support to other units, so you will start the game behind your opponent, that can try to exploit this initial advantage.
So, you need to summon fast, to recover the gap and turn in your favor the war of attrition.

TWO:

To recover that gap, You will need 2 things: hitting power and bodies.

How to conjure these things? it will depends on your initial list: if you already have some hitters (thunderquake?), then go firstly for units to fill the battlefield (skinks and so on).
If you already have some battleline troops that can act as shield, then go asap for some real punch, and only after that you can summon lots of cheap bodies to swarm the battlefield and take objectives, while your opponent is dealing with your hitters.

THREE:

Play aggressively.
The advantage of the opponent is to have more power than you in the first stage of the game.
Throw at him what you have, don't let him outmanoveur you. The things you lose will be conjured back, but if you manage to force him to play a defensive game, you've already won a half of the battle.

Well, not always this will be doable, as sometime you will be forced to defend yourself, but you should never start with a defensive approach.

FOUR:

The last but not least important advice is: dont be fixed with things. The main force of the summoning strategy is the total versatility of it. It's a fantastic tool that can and must be adapted on the fly.
It's good to have a couple of key units that you want to summon on the battlefield, but for the rest you should see at the moment what's needed the most.
Play your summons alongside the abilities of our army (teleport, constellation and so on), find the synergies and you'll be golden.

FIFTH:

ohh, I've got another one.
Your army depends heavily on the Slann. Protect your general at all costs, or you will almost surely lose the game..
This can be done in a number of ways: cover, Look-out-sir, command ability to reroll saves vs shooting, Eternity Warden, defensive LoSaT, aggressive play to force your opponent upon more immediate threats, artefact to come back to life. Just do what must be done.

I'd like to add one note to the Terradons though:
If you use them with Javelins they are nice for harassment because they can shoot in the turn they are summoned.
With bolas they can't, but they are still nice because your opponent knows they will drop bombs, shoot, and go into melee the next turn.

Leaving aside the EotG, a heavy summoning list, will include Slann, AB, Vortex, a Starseer and a Cogs (that will be casted by the skink, to be used by the Slann).
In 2 turns, if you totally forego casting, you can collect up to 29 + 2d3 CCPs.

Click to expand...

Why specifically a starseer?

Saurus warriors:
There's 1 specific scenario in which they work. Driving an enemy unit of an objective while also providing bodies. The other saurus are better at driving the enemies away, but provide less bodies. Skinks provide more bodies but are utterly hopeless at driving an enemy away. Saurus warriors are somewhere in between both extremes and this is about the only possible use in terms of summoning.

Saurus guards:
They actually have a decent use-case now that they can be freely summonend.
- They are sturdy enough that they require a decent amount of firepower to be wiped out.
- They have good enough attacks that when left on their own they'l wreck some havoc. Especially against the "weaker" troops that generally will be contesting objectives.

This allows them to fairly easily contest objectives. Forcing an opponent to send reinforcements or concede the objective.
Also, their all-round good stats, and especially their potential to be nigh immortal unless faced with mortal wounds means that what your opponent sends to deal with them is going to be fairly good. Allowing them to very very effeciently work as target saturation in certain situations. An arcane bolt shot at them is an arcane bolt not shot at your carnosaur. This'l work especially brilliantly if you already started with an eternal starhost. Your opponent will have noticed them to be sturdy so he'l be more eager to throw his heavy firepower at them.

And lastly, if for whatever reason your opponent no longer has mortal wounds to dish out. And you can get them near a skink priest or throw a mystic shield on em, they're hilariously difficult to remove even without the starhost bonusses.

In short they can do the following:
- Target saturation
- Contest objectives/be a general nuisance
- Be hilariously difficult to remove should your opponent have lost acces to his mortal wounds.

Saurus Knights
I'd list them as "good". They're the most rounded of our various battleline and thus the least dependent on their buffs. They're very similar in terms of power to terradons, except more sturdy in exchange for not having the bombs.

20 Saurus warriors
Probably the best objective grabbers we have where both fighting and bodies is concerned. Knights & guards can't be summonend in anywhere near the sa,e quantities & skinks are just too terrible in combat. Unlike the 10 man unit it has a clear niche as the difference with the other options is now much more pronounced. If however you don't have to fight over the objective, or you can make do with the 5 man in a guard or knight squad to actually control it then any of the other options is better.

Saurus guards:
They actually have a decent use-case now that they can be freely summonend.
- They are sturdy enough that they require a decent amount of firepower to be wiped out.
- They have good enough attacks that when left on their own they'l wreck some havoc. Especially against the "weaker" troops that generally will be contesting objectives.

Click to expand...

We're still talking about a 5-wounds unit. Roll poorly with the save and goodbye.
But yeah, I will raise them to "suboptimal"

Saurus Knights
I'd list them as "good". They're the most rounded of our various battleline and thus the least dependent on their buffs. They're very similar in terms of power to terradons, except more sturdy in exchange for not having the bombs.

20 Saurus warriors
Probably the best objective grabbers we have where both fighting and bodies is concerned. Knights & guards can't be summonend in anywhere near the sa,e quantities & skinks are just too terrible in combat. Unlike the 10 man unit it has a clear niche as the difference with the other options is now much more pronounced. If however you don't have to fight over the objective, or you can make do with the 5 man in a guard or knight squad to actually control it then any of the other options is better.

Click to expand...

still a niche use, but I'll add in the description. tnx for the input.

We're still talking about a 5-wounds unit. Roll poorly with the save and goodbye.
But yeah, I will raise them to "suboptimal"

Click to expand...

With a 4+ base save and protection from rend, as well as a relativly easy option to get to a 3+ save that shouldn't be too much of an issue.
Yeah, they're not going to do much to slow down a rampaging deathstar, but an objective grabber is probably not even going to scratch em in 1 round of combat. And they're good enough that they can hold their own even against some more powerfull melee opponents.

But what I think is most important is that they can't be ignored. With 11 3+/3+/-1/1 attacks they pack a decent punch. That combined with their decent save means your opponent will have to dedicate something significant to dealing with them or relinquish control of the area.

Terradons cause 5 melee and 2 ranged hits per round, totalling 12 per turn, Knights do 6-7 melee hits per round totalling 12-14 per turn. Terradons have 9 wounds, Knights 10. Both have a 5+ save, but Knights have rend protection. Terradons have their bombs, Knights their banners & drums and charge bonus.
Also, Knights can actually synergize with command abilities and our starpriest. Terradons cannot. Which is stupid, but we'l have to make due.

Terradons will do a tad better in overal damage thanks to their bombs, Knights are a bit sturdier with 1 more wound and rend protection and have some additional power via their banners. If the Knights get support with some command abilities and a starpriest they rapidly pull ahead though.

Also, minor sidenote, but why exactly can we only summon in our movement phase? I get that summoning + moving would probably be too much. But this also means we miss out on a lot of potential buffs and they could've just said "can't move in the following movement phase" to fix that. Has there ever been an explenation given for that?

Also, minor sidenote, but why exactly can we only summon in our movement phase? I get that summoning + moving would probably be too much. But this also means we miss out on a lot of potential buffs and they could've just said "can't move in the following movement phase" to fix that. Has there ever been an explenation given for that?

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It is for balancing purposes. GW doesn't want something to enter play and be fully buffed and synergized the turn it arrives. Basically, GW dislikes being able to "deepstrike" (summon or otherwise) a unit into to play with a high chance of it being effective the turn it is placed. It is why we have seen so many FAQs and Errata directed at limiting the on-turn power of placing units after set up. In GWs mind they want both players to be able to interact with new units arriving. That way the person deepstriking isn't able to eliminate their target and prevent counter play.

It is for balancing purposes. GW doesn't want something to enter play and be fully buffed and synergized the turn it arrives. Basically, GW dislikes being able to "deepstrike" (summon or otherwise) a unit into to play with a high chance of it being effective the turn it is placed. It is why we have seen so many FAQs and Errata directed at limiting the on-turn power of placing units after set up. In GWs mind they want both players to be able to interact with new units arriving. That way the person deepstriking isn't able to eliminate their target and prevent counter play.

Click to expand...

I guess that makes sense for ranged troops, or for melee troops that can reliably charge. But it's fairly lame for troops that are unlikely to make the charge, but will probably be shot at, and rather stupid for support troops.

meh… they should make the game last significantly longer in that case, or well more turns not necesarly longer. With only 5 turns deepstriking is kind of an all or nothing deal unless you happen to do it turn one simply due to how much time the unit spends not existing. No idea how they should achieve it, but it would help with making deepstriking feel powerfull/usefull without them needing to immeadiatly be devestating.